Frontend Platform Engineer

OLX

Location: Poland
Job Type: full-time
Salary: Unknown
Posted: September 11, 2025

Job Description

At OLX, we work together to build a more sustainable world through trade.

We make it safe, smart, and convenient to buy and sell cars, find housing, get jobs, buy and sell household goods, and more. Our colleagues around the world help to serve millions of people around the world every month, through its well-loved consumer brands including OLX, Otodom, Property24.

Join OLX and see how far you can go.

Join Our Team as a Frontend Platform Engineer! Join one of our cross-functional teams in Motors, Real Estate, OLX Classifieds or Platforms, working remotely from Poland. As part of our 1,000+ tech team across multiple locations, you’ll collaborate with engineers, SREs, and product teams to build scalable, high-impact solutions, while reporting to an Engineering Manager who will support your growth and impact.

Our platform leverages a modern Javascript tech stack (modules federation, TypeScript, React, Emotion, Playwright), adhering to industry best practices and leveraging robust CI/CD workflows through GitLab pipelines. This distributed FE system is hosted on AWS, ensuring high reliability and scalability.

Who we are looking for:

- Someone with a strong understanding of frontend platform architecture and experience building tools or frameworks that scale across teams, and skilled in designing decoupled systems to simplify large-scale applications.

- A developer who’s enthusiastic about knowledge sharing, mentoring, and fostering collaboration within engineering teams (organizing workshops, driving initiatives, contributing to RFCs).

- A technical expert with hands-on experience in Server Side Rendering (SSR), CI/CD pipelines, and modern build tools, focused on delivering high-performance, scalable, and efficient web applications.

- A detail-oriented problem-solver with strong observability skills, with a focus on monitoring, logging, and debugging to maintain reliability and system health.

- Someone with a track record of tackling challenges like legacy codebase migration, decoupling dependencies, and improving maintainability.

- A self-starter with a strong sense of ownership and responsibility, confident in leading projects and delivering high-quality solutions from start to finish.

What you will be doing:

- Designing and maintaining the frontend platform architecture, frameworks, and tools used across the organization.

- Leading efforts to adopt and optimize micro frontend architectures for scalability and team autonomy.

- Building and improving CI/CD pipelines to streamline build processes and deployments.

- Supporting the migration of legacy codebases into modern, decoupled systems while maintaining business continuity.

- Developing build tools and automated solutions to enhance the engineering team’s productivity.

- Collaborating with cross-functional teams to ensure seamless infrastructure integration and scalability.

- Taking ownership of platform-wide initiatives, promoting best practices, and guiding the engineering teams in achieving technical excellence.

Our Hiring Process:

1). Recruiter Interview

2). Live Coding

3). System Design

4). People Manager Interview

Our Benefits:

Monthly salary and an annual bonus (15%)

Training and conference budget and free access to Udemy courses

A benefits package with 300 points on the Mybenefit platform per month, private medical care provided by Luxmed, Ask Henry services, and much more

IP rights’ costs

100% remote work (as well as the possibility of working from our offices in Poznan and Warsaw)

If you think this is the role for you, send your application in English and let’s talk!

🎯 Who is this job for?

This role suits a Senior Frontend Platform Engineer with deep experience in TypeScript, React, SSR, CI/CD pipelines, and frontend architecture. Candidates should be adept at designing scalable systems, working with micro frontends, and leading migration from legacy codebases. Strong mentoring skills, a focus on observability, and experience with AWS-hosted applications are essential.

💬 Potential Interview Questions

How does Webpack Module Federation enable micro frontends at scale, and how do you manage shared dependencies?
It lets apps expose/consume modules at runtime, avoiding hard rebuild-time coupling. Use shared with strict version ranges/singleton for React, enforce semver via a platform lockfile, and audit remotes with runtime version checks.
How would you implement SSR for a micro frontend architecture and ensure safe hydration?
Run SSR per-remote on the server (or an aggregator) and serialize a manifest of loaded remotes/chunks. Use React 18 streaming + selective hydration and align router/state boundaries so each MFE hydrates only its DOM island.
What’s your approach to CI/CD in GitLab for dozens of MFEs?
Adopt workspace-based monorepos (pnpm/Nx/Turborepo), cache deps/builds, and use change detection to run only affected pipelines. Publish remote artifacts as versioned GitLab artifacts, then promote via environment-scoped deploy jobs with canaries.
How do you make Emotion performant and consistent across MFEs (including SSR)?
Extract critical CSS on the server, share a stable CacheProvider/@emotion/cache key to avoid duplication, and enable @emotion/babel-plugin for static extraction and labels. Standardize theming tokens so styles don’t drift per-remote.
How do you observe and debug a distributed frontend platform?
Instrument RUM (Core Web Vitals, SPA navigations), capture errors with Sentry/OpenTelemetry, and propagate correlation IDs across page → remote → API. Build dashboards per domain and alert on regressions (e.g., INP, error rate, asset 4xx/5xx).
How do you route and share app shell concerns across MFEs?
Keep a platform shell owning global router, auth, and layout; remotes render within defined slots. Pass capabilities via context adapters (e.g., analytics, i18n) and version those contracts to avoid implicit coupling.
How do you test MFEs reliably (unit → E2E)?
Unit-test components with Jest/RTL, contract-test exposed modules (types + runtime schema), and stub remotes in integration tests. Use Playwright for E2E with stable test IDs and visual diffs; run smoke suites per remote on deploy.
How would you migrate a legacy SPA into MFEs without downtime?
Apply the Strangler pattern: ship a shell, proxy specific routes to new remotes, and incrementally carve out features. Add anti-corruption layers for shared state/APIs and run telemetry-based canaries before flipping traffic.
What security controls do you enforce on a federated frontend?
Strict CSP (no unsafe-inline), SRI for static assets, Trusted Types to block XSS sinks, and dependency pinning with provenance checks. For dynamic remotes, whitelist origins and consider sandboxed iframes for untrusted modules.
How would you host and release at scale on AWS?
Serve static assets from S3 behind CloudFront, use edge functions for header/routing rewrites and canaries, and atomic releases via versioned asset manifests. Enable long-lived caching with content hashing and fast invalidations on manifest changes.

📋 Job Summary

OLX is hiring a Frontend Platform Engineer to design scalable architecture, improve CI/CD pipelines, and lead the migration of legacy systems—all remotely from Poland. You'll work with React, TypeScript, Emotion, SSR, and GitLab CI/CD in a micro frontend setup hosted on AWS. Enjoy a 100% remote role with a 15% annual bonus, training budget, and top-tier benefits. Join a global, tech-forward team shaping secure, high-performance platforms for millions of users.